1. Field of Invention
This invention relates to sailboat sails, especially to a novel construction of high performance sails for propulsion of racing and cruising sailboats, sailboards, iceboats and land sailing craft.
2. Description of Prior Art
High performance sails have these fundemental characteristics: light weight, high strengh and low stretch. The degree to which these characteristics are achieved, along with the sails cut and workmanship, determines the ultimate performance of the sail. Heretofore, high performance sails, which is a very crowded art, have been produced to achieve these characteristics by using one of the following methods; 1) either a single woven sailcloth, such as Dacron, Kevlar, Nylon or Spectra; or a laminated composite sailcloths, consisting predominately of Mylar film backed with Dacron, Kevlar or Spectra woven material( Mylar is a film and Dacron is a fabric thread material of a polyester polymer, Kevlar is a fabric thread material of an aramid polymer, and Nylon is a fabric thread material of polyamides; Mylar, Dacron, Kevlar and Nylon are trademarks of the Dupont Company of Wilmington, Del.; Spectra is a polyolefin polymer fiber and Spectra is a trademark of the Allied Corperation of Morristown, N.J.); with a panel orientation aligning the major force lines with warp threads (since they will bear loads better than the weft threads); or 2) by laminating individual threads, aligned with the major force lines on a plurality of panels interconnecting the head, tack and clew, in between a layer of Mylar and another layer of Mylar or a layer of woven Dacron, Kevlar or Spectra material; or 3) finally by using lighter weight laminate or woven sailcloths reinforced with an intricate layout of structural members sewn to sail interconnecting the head ,tack and clew of the sail to bear the load forces of the sail.
All of these construction techniques are very labor and materials intensive with much wastage using very expensive woven and laminated sailcloths resulting in high priced sails. Other problems with these techniques exist, including: 1) the problem of laminate sails delaminating, resulting in expensive repairs or complete loss of use of the sail; 2) Kevlar, even with its high strength to weight characteristic, is susceptiable to distortion and breakdown due to flexing of the material; And 3) a panal width is usually limited to a maximum of 36 inches for most sailcloths, requiring broadseaming and an large number of panels in the sail.